Hi all, just joined. Having my new (to me) IT465 cyl bored and was wondering what a good oil for aircooled trail / woodsriding might be. Going to use Pennzoil aircooled mineral to seat the rings, but would like a higher performance oil after that. I think most modern oils are formulated tor liquid cooled power valve engines. Only oil I can think of for perf aircooled is B-R MC-1. Has anyone used Maxima K2 for medium performance riding? (it seems to be the only ester syn with a lower flash and decent recommended ratio's) I prefer 32:1. good ring seal. Of course the jetting will need to be set up right.
Not trying to start an oil war, just advice specifically for 50/50 on/off the pipe trail riding on aircooled big bore dinosaurs

Also wondering if anyone has had luck running these bikes on 91 premium (the best I can get is shell vpower 91). There's no race gas available in my area (BC) Anybody had any experience with Klotz Hitrate?

you're over thinking it. 32:1, synthetic.
91 octane is fine. flashpoint is negligible on this motor...

[QUOTE=KX50002;23894275]I run 32:1 Blendzall in my KX500(water cooled) and YZ 400 (air cooled) with no problems, and it smells great. Have run this in every 2 stroke I've owned for about 25 years now.

Thanks guy's. Yeah, probably overthinkin' it (you get bored waiting for parts) The previous owner ran Royal purple at 50:1 and although the engine was clean, there was quite a bit of wear on the cylinder / piston (no scratching or scoring though) Maxima K2's available all over here, so I'll likely go with that. I might give a castor a try later as well, but I don't think I'm "on it" hard enough. I heard Blendzall's good stuff though. I was wondering about the octane because I needed to resurface the head and cylinder (about .007" on each) and given today's "questionable" pump gas.... Maybe I'll set the timing a little conservative at first.

I was wondering about the octane because I needed to resurface the head and cylinder (about .007" on each) and given today's "questionable" pump gas.... Maybe I'll set the timing a little conservative at first.

the 465 doesn't ping like the 490 motor - if it's jetted right, it should be fine on good octane. was the cylinder surface and head both warped? conservative timing may not be needed, you will find out if you can get it to ping.

the 465 doesn't ping like the 490 motor - if it's jetted right, it should be fine on good octane. was the cylinder surface and head both warped? conservative timing may not be needed, you will find out if you can get it to ping.

Yeah, they were both warped so I used the thick glass / 500 grit method mentioned in the yam manual for resurfacing (worked really well!) The jetting as I found it was 370 main, 40 pilot, stock needle/jet 2nd clip position from top (running 50:1). I'll probably start with a 380, 40 pilot, and the needle in the 3rd position running 32:1.

I'll make her run as sharp as I can this year with the mikuni vm, but I always had thoughts of using a different carb. I like the Keihin pwk38 used on the 90's kx250 (non airstriker). You can get 'em used pretty cheap. The spigot would need to be turned down to 43mm from 46. I like to mess around with old bikes and see how great they can be with a bit of experimentation. I'll definitely check the squish clearance though and change the crank seals before I fire it up.

So how much does an oils flash point actually play into the way it works for a given riding style? There are tons of quality oils available; some have lower numbers, some have higher numbers, and I haven't seen manufacturers use this data for anything other than their req'd msds's. If a bikes combustion temperature is correct (jetting) then maybe that number doesn't really mean anything? If the temp on the cylinder wall is higher (like an aircooled bike) than the flash point of the oil, then maybe it might be important? Thought I would mention it, since I noticed it brought up on some other sites (usually in regards to "spooge") I'm definitely not a chemistry expert

So how much does an oils flash point actually play into the way it works for a given riding style? There are tons of quality oils available; some have lower numbers, some have higher numbers, and I haven't seen manufacturers use this data for anything other than their req'd msds's. If a bikes combustion temperature is correct (jetting) then maybe that number doesn't really mean anything? If the temp on the cylinder wall is higher (like an aircooled bike) than the flash point of the oil, then maybe it might be important? Thought I would mention it, since I noticed it brought up on some other sites (usually in regards to "spooge") I'm definitely not a chemistry expert

flashpoint is much more of a factor for power valves gumming up.. with pv motors, if the flashpoint is too high, it could gum up the pv... on air cooled motors, if it's jetted correctly or even remotely close, and the oil mix is not crazy rich it's pretty much a non issue.

don't know what style of woods/trail riding you'll be doing, but if it's tight/slow stuff, you will be at small throttle openings a lot, and probably gonna lug it a bunch. make sure the pilot/slide cutaway/needle position are jetted cleanly, or it could load up pretty good. it's a lot of motor, as long as you rev it once in a while it'll be fine.. keep in mind it is not a 465cc chainsaw, you will not be running it wide open much, it's a torque spurter, not a rev monster :) if you find you are revving the shit out of it, shift up. it'll yank ya around nicely.

flashpoint is much more of a factor for power valves gumming up.. with pv motors, if the flashpoint is too high, it could gum up the pv... on air cooled motors, if it's jetted correctly or even remotely close, and the oil mix is not crazy rich it's pretty much a non issue.

don't know what style of woods/trail riding you'll be doing, but if it's tight/slow stuff, you will be at small throttle openings a lot, and probably gonna lug it a bunch. make sure the pilot/slide cutaway/needle position are jetted cleanly, or it could load up pretty good. it's a lot of motor, as long as you rev it once in a while it'll be fine.. keep in mind it is not a 465cc chainsaw, you will not be running it wide open much, it's a torque spurter, not a rev monster :) if you find you are revving the shit out of it, shift up. it'll yank ya around nicely.

Just a mix of riding; forest, rocks, logging roads, the odd hillclimb, sandwash. Nothing that's sustained like dunes or desert. Thought it may help others if there was more detailed info about what may or may not work and different things you hear about like flashpoint. That makes sense about powervalves. I guess if you were to run a pv's at lower rpms then flash and detergency would be more of an issue. The one oil I'd love to try is Klotz R50, which is pretty heavy oil, probably not too great for low rpm work, but without a pv and sharp jetting, might get away with it I know the slide cutaway makes a pretty dramatic difference, once I get riding it I'll try to fig out if I need to change it. The one I have is a 2.0 The pipe is stock (great shape) and the silencer is aftermarket old school (can't find the mfg name), but I just repacked it, it was pretty clean, (probably due to the 50:1 )